A thumb is an implement which is typically pivotally mounted on the underside of a stick of an excavator. The thumb opposes and cooperates with the excavator bucket for grasping material held between the bucket and the thumb. Stiff link thumbs are fixed relative to the stick, as opposed to hydraulically actuated thumbs. In use, the bucket is curled and uncurled relative to the stick to grasp and hold material between the bucket and thumb. Stiff link thumbs may be connected to the stick with a strut whose position can be adjusted to permit adjustment of the angle of the thumb relative to the stick. The strut may consist of a rigid link detachably securable by one or more pins to one of a number attachment points provided on the stick.
Typically, with current excavator thumb assemblies, to lock the thumb into a working position, one or more pins must be frictionally received through one or more holes on the link and one or more corresponding holes on the bracket or attachment point on the stick. Proper alignment, however, can be difficult since a typical excavator thumb assembly can exceed 600 pounds while the link can exceed 100 pounds.
U.S. Pat. No. 6,203,267 discloses a thumb assembly with a rigid strut connected to a bracket by a pin. The strut includes a T-shaped end that is received in a complementary slot in the bracket. While the T-shaped end and the slot will support the weight of the strut and thumb when the pin removed which can aid in connecting the strut to the bracket, the thumb assembly disclosed in the '267 patent adds significant complexity and cost to the thumb design and does not provide a visual indication when the strut and bracket are sufficiently aligned.
The present disclosure is directed to overcoming one or more of the problems as set forth above.